Well anything can work, but that doesn't mean it's anywhere close to optimal IMO. If I remember correctly, Arnold S's advanced workout in that infernal book featured working out 6 days per week with only a single day off and a megaton of volume. It also features using a pyramid scheme for just about everything which is also garbage IMO. That's like saying, "I'm going to grab the latest FLEX magazine and do "Ronnie Coleman's Back Routine" and get terrific results! I can't wait to try it!"
The death of modern bodybuilding
That's a bad analogy. No way you can compare a machine with a fixed path of motion to a free weight compound exercise. Then again, that really doesn't have anything to do with my point either. My point was that you cannot isolate portions of your muscles.
I was just giving an example that the flat bench stimulates the entire pectoral muscle. I'm not saying to adopt the flat bench as your ONLY exercise, drop the rest, and go balls to the wall for the next hundred years.
What I AM saying is that you don't need do do a full assault with an arsenal of 8 different exercises from every concievable angle to work the SAME muscle. You can't take a marker, divide your chest up into 6 different pieces and strategically work each little piece!
Instead, you can pick up something like 5x5 flat bench, then 2-3 x 10 incline DB, and move on to another bodypart...Essentially working your pectoral muscle as a whole.
There's a lot of things to take into account such as frequency, set/rep schemes, ect. Something like Bill Starr's 5x5 features flat bench twice a week, once ramping up to a top set of 5, once 5 sets of 5 with the same weight. You could do inclines instead of flat one day as per AM's version. If you got an adequate amount of volume and frequency with 1-2 compound lifts, in this case flat and incline or decline bench, you certainly won't need cable crossovers or incline DB flyes to work your "inner-upper" pecs, especially since there really is no such thing.